Mulch calculator

Enter the shape of the bed, the depth you want and what is left of last year's mulch. We work out the cubic yards and count the bags.

200 sq ft at 3.0 in of new mulch is 1.85 cu yd (50.0 cu ft), or 25 bags of 2 cu ft.

Cubic feet: 50.0 cu ft
Cubic yards, bulk: 1.85 cu yd
One cubic yard covers: 108 sq ft at 3.0 in
One 2 cu ft bag covers: 8.0 sq ft at 3.0 in
Bulk cost: $152.96 for 1.85 cu yd at $82.60 a cu yd
Bag cost: $83.25 for 25 bags at $3.33 a bag

Prices are shelf prices at The Home Depot, Hamilton Mill store, before tax and delivery: 10 cu. yd. Bulk Hardwood Mulch (model BKHM10), read Nov 6, 2026, and Vigoro 2 cu ft brown mulch, read Oct 25, 2026. The bag price shows for the 2 cu ft bag only. Bulk mulch is hardwood; dyed and other mulches cost more.

Bulk mulch is sold by the cubic yard, about 13 to 14 bags of 2 cu ft each. Past two or three yards, ask a landscape yard for its delivered price and compare it with the bags.

Building the bed first? Topsoil calculator

Cubic yards, tons and bags of topsoil for a new bed or lawn.

Planning figures. Bag sizes vary; read the cubic feet printed on the bag you buy.

How the mulch calculator works

Enter the shape of the bed, the depth of mulch you want and, if you are topping up, how much old mulch is still there. The mulch calculator takes the difference, turns the area and depth into cubic feet and cubic yards, and counts the bags at the size you pick. Rectangles, L-shaped beds and circles around a tree all work.

Cubic feet and cubic yards

Square feet times the depth in inches over 12 is cubic feet. The 10x20 ft example at 3 in is 200 x 3 / 12 = 50 cu ft, and 50 / 27 = 1.85 cu yd.

Bags

Most bagged mulch is 2 cu ft, so divide the cubic feet by 2 and round up: 25 bags for the example. A cubic yard is 13.5 of those bags, which is why a bed past two or three yards is usually cheaper and quicker as a bulk delivery.

Topping up an old bed

Mulch breaks down, so most beds need a refresh each year rather than a full depth. With 1 in left and 3 in wanted, the same 10x20 ft bed takes 17 bags instead of 25. A ring of mulch 6 ft across around a tree, at 3 in, is 7.1 cu ft, 4 bags.

Mulch by bed size and depth

Bed and depth	Cubic feet	Cubic yards	2 cu ft bags
10x10 ft, 2 in	16.7	0.62	9
10x10 ft, 3 in	25.0	0.93	13
10x20 ft, 3 in	50.0	1.85	25
4x40 ft border, 3 in	40.0	1.48	20
20x20 ft, 3 in	100.0	3.70	50
20x30 ft, 4 in	200.0	7.41	100

Mulch around a patio

A bed of mulch along a patio or a path softens the edge and keeps soil off the pavers. Set the paver edge restraint first, then the bed. If you are building the bed from bare ground, the topsoil calculator counts the soil under it, and the gravel calculator covers a stone border instead of bark.

Where the numbers come from

One cubic yard is 27 cubic feet. The 2 to 4 in depth and the 3 in start are editorial, the range garden extension services commonly give for wood mulch. Bag sizes are the volumes printed on the bags; the prices are shelf prices at The Home Depot, Hamilton Mill store: hardwood bulk mulch at $82.60 a cu yd, read Nov 6, 2026, and Vigoro 2 cu ft brown mulch at $3.33 a bag, read Oct 25, 2026, before tax and delivery. They change by the season and the store.

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Questions

Anything else? Write to us or see every calculator.

Questions people ask

Multiply the length by the width of the bed in feet, then by the depth in inches divided by 12, for cubic feet. Divide by 2 for 2 cu ft bags, or by 27 for cubic yards. A 10x20 ft bed at 3 in is 50 cu ft: 25 bags or 1.85 cu yd.

108 sq ft at 3 in deep, 162 sq ft at 2 in and 81 sq ft at 4 in. A cubic yard is 27 cubic feet, so divide 324 by the depth in inches.

At 3 in deep, 13 bags of 2 cu ft (25 cu ft). At 2 in it is 9 bags.

2 to 4 in over beds and around trees; we start at 3 in. Deeper than that can keep air and water from the roots, and mulch piled against a trunk or a stem invites rot, so leave a few inches clear.